Ilungiswa njani i-hydroxyethyl cellulose?

I-Hydroxyethyl celluloseyi-cellulose derivative ebalulekileyo. Ngenxa yeenzuzo zezinto eziluhlaza ezininzi, ezivuselelekayo, ezinokubola, ezingenabungozi, ezihambelana kakuhle ne-biocompatibility, kunye nesivuno esikhulu, uphando kunye nokusetyenziswa kwayo kuye kwatsala ingqalelo enkulu. . Ixabiso le-viscosity liyi-index yokusebenza ebaluleke kakhulu ye-hydroxyethyl cellulose. Kweli phepha, i-hydroxyethyl cellulose enexabiso le-viscosity elingaphezulu kwe-5×104mPa·s kunye nexabiso lothuthu elingaphantsi kwe-0.3% yalungiswa ngendlela yokwenziwa kwe-liquid-phase ngokusebenzisa inkqubo ye-alkalization kunye ne-etherification enamanyathelo amabini.

Inkqubo ye-alkalization yinkqubo yokulungiselela i-alkali cellulose. Kule phepha, kusetyenziswa iindlela ezimbini ze-alkalization. Indlela yokuqala kukusebenzisa i-acetone njenge-diluent. Izinto eziluhlaza ze-cellulose zisekelwe ngokuthe ngqo kwi-concentration ethile yesisombululo samanzi se-sodium hydroxide. Emva kokuba kwenziwe i-basification reaction, kongezwa i-etherifying agent ukuze kwenziwe ngqo i-etherification reaction. Indlela yesibini kukuba izinto eziluhlaza ze-cellulose zifakwe kwi-aqueous solution ye-sodium hydroxide kunye ne-urea, kwaye i-alkali cellulose elungiselelwe ngale ndlela kufuneka icinezelwe ukuze kususwe i-lye engaphezulu ngaphambi kokuba i-etherification reaction. I-alkali cellulose elungiselelwe ngeendlela ezahlukeneyo ihlalutywe yi-infrared spectroscopy kunye ne-X-ray diffraction. Ngokweempawu zeemveliso ezilungiselelwe yi-etherification reaction, indlela yokukhetha iyamiselwa.

Ukuze kuchongwe eyona nkqubo ilungileyo yokwenziwa kwe-etherification, indlela yokusabela ye-antioxidant, i-lye kunye ne-glacial acetic acid kwi-etherification reaction yahlalutywa kuqala. Emva koko kwakhiwe inkqubo yovavanyo ye-single factor reaction, kuchongwe izinto ezinefuthe elikhulu ekusebenzeni kwe-hydroxyethyl cellulose elungisiweyo, kwaye kusetyenziswe i-viscosity yesisombululo samanzi se-2% semveliso njengesalathiso sokubhekisa. Iziphumo zovavanyo zibonisa ukuba izinto ezifana nesixa se-diluent esikhethiweyo, ubungakanani be-ethylene oxide eyongeziweyo, ixesha le-alkalization, ubushushu kunye nexesha le-reaction yokuqala, ubushushu kunye nexesha le-reaction yesibini zonke zinempembelelo enkulu ekusebenzeni kwemveliso. Iskimu sovavanyo lwe-orthogonal esinezinto ezisixhenxe kunye namanqanaba amathathu saqulunqwa, kwaye i-effect curve ethathwe kwiziphumo zovavanyo inokuhlalutya ngokubonakalayo izinto eziphambili nezesibini kunye nomkhwa wempembelelo yento nganye. Ukuze kulungiselelwe iimveliso ezinexabiso eliphezulu le-viscosity, kwaqulunqwa iskimu sovavanyo esilungisiweyo, kwaye iskimu esifanelekileyo sokulungiselela i-hydroxyethyl cellulose ekugqibeleni samiselwa ngeziphumo zovavanyo.

Iimpawu ze-viscosity ephezulu elungiselelweyoi-hydroxyethyl celluloseZihlalutywe zaza zavavanywa, kuquka ukuqinisekiswa kwe-viscosity, umxholo wothuthu, ukuhanjiswa kokukhanya, umxholo wokufuma, njl.njl., nge-infrared spectroscopy, i-nuclear magnetic resonance, i-gas chromatography, i-X-ray diffraction, uhlalutyo lwe-thermogravimetric-differential thermal kunye nezinye iindlela zokuchonga zisetyenziselwa ukuhlalutya nokuchonga isakhiwo semveliso, ukulingana okutshintshiselanayo, i-molar substitution degree, i-crystallinity, uzinzo lobushushu, njl.njl. Iindlela zovavanyo zibhekisa kwimigangatho ye-ASTM.

I-Hydroxyethyl cellulose, i-cellulose ephuma kwi-cellulose ebalulekileyo, itsale ingqalelo ngenxa yezixhobo zayo ezininzi eziluhlaza, ezivuselelekayo, ezinokubola, ezingenabungozi, ezihambelana ne-biocompatible, kunye nesivuno esiphezulu. I-viscosity ye-hydroxyethyl cellulose luphawu olubaluleke kakhulu lokusebenza kwayo. I-viscosity ye-hydroxyethyl cellulose elungisiweyo ingaphezulu kwe-5×104mPa·s, kwaye umxholo womlotha ungaphantsi kwe-0.3%.

Kule phepha, i-hydroxyethyl cellulose ene-viscosity ephezulu yalungiswa ngendlela yokwenziwa kwe-liquid-phase ngokusebenzisa i-alkalization kunye ne-etherification. Inkqubo ye-alkalization kukulungiselela i-alkali cellulose. Khetha kwiindlela ezimbini ze-alkalization. Enye kukuba izinto ze-cellulose zi-alkalization ngqo nge-acetone njenge-diluent kwisisombululo se-sodium hydroxide samanzi, emva koko zenze i-etherification reaction nge-etherifying agent. Enye kukuba izinto ze-cellulosic zi-alkalization kwisisombululo se-sodium hydroxide samanzi kunye ne-urea. I-alkali egqithisileyo kwi-alkali cellulose kufuneka isuswe ngaphambi kokuba i-reaction iqale. Kule phepha, ii-alkali celluloses ezahlukeneyo zifundwa yi-infrared spectroscopy kunye ne-X-ray diffraction. Okokugqibela, indlela yesibini yamkelwe ngokweempawu zeemveliso ze-etherification.

Ukuze kuchongwe amanyathelo okulungiselela i-etherification, indlela yokusabela ye-antioxidant, i-alkali kunye ne-glacial acetic acid kwinkqubo yokutya ifundwe. Izinto ezichaphazela ukulungiswa kwe-hydroxyethyl cellulose zichongiwe ngovavanyo lwe-single factor. Ngokusekelwe kwixabiso le-viscosity yemveliso kwisisombululo samanzi se-2%. Iziphumo zovavanyo zibonisa ukuba umthamo we-diluent, ubungakanani be-ethylene oxide, ixesha le-alkaliization, ubushushu kunye nexesha lokuphinda kufakwe amanzi emzimbeni okokuqala nokwesibini kunempembelelo enkulu ekusebenzeni kwemveliso. Indlela yezinto ezisixhenxe kunye namanqanaba amathathu yamkelwe ukumisela indlela yokulungiselela engcono.

Sihlalutya iimpawu ze-preparedi-hydroxyethyl cellulose, kuquka i-viscosity, uthuthu, ukuhanjiswa kokukhanya, ukufuma, njl. Ukuchazwa kwesakhiwo, i-homogeneity etshintshayo, i-molarity yokutshintsha, i-crystallinity kunye nokuzinza kobushushu kuxoxwe nge-infrared, i-nuclear magnetic resonance, i-gas chromatography, i-X-ray diffraction, i-DSC kunye ne-DAT, kwaye iindlela zovavanyo zamkela imigangatho ye-ASTM.